The invention relates to agricultural seeders, such as hoe openers and seeding tools used in farming operations to distribute seeds into the soil.
Generally, precision hoe openers are mounted to the frame of an implement which is towed behind a tractor. These openers may include a ground engaging tool that opens the soil, providing a path for seed deposition into the soil. After the seed is deposited, the ground engaging tool may be followed by a packer wheel that packs the soil on top of the deposited seed. The packer wheel may be rigidly mounted behind the ground engaging tool via a structural member or rear frame. Thus, the ground engaging tool and packer wheel generally move together with the same upward and downward motion. This vertical motion, somewhat independent of the implement frame, allows for more precise placement of seed in the soil.
Unfortunately, existing precision hoe openers do not adequately address the need for height variation over terrain during seeding, or for transportation when not seeding. It is generally undesirable to pull the hoe opener through soil when merely transporting the opener from one location to another. In addition, during seeding, existing openers do not provide adequate vertical motion of the opener and related assembly without compromising the load on the ground engaging tool and packer wheel. As a result, variations in the terrain can result in drastic changes in the packing force of the packer wheel on the terrain being seeded by the opener and, also, the draft force of the terrain on the ground engaging tool. In turn, this variation in ground opening force and packing force can result in non-uniform seeding depths and packing density in the terrain being seeded.
The distance between the packer wheel and ground engaging tool can also affect the seeding accuracy of the opener apparatus. Existing precision hoe openers have a fixed distance between the packer wheel and ground engaging tool. A greater distance between the components will cause variations in the terrain to affect the force on the opener or packer wheel to an even greater degree. This will also result in non-uniform force applied to the soil by the two components, which reduces seeding accuracy.
Existing precision hoe openers also require substantial force to raise the opener assembly, including the ground engaging assembly and packer wheel. This requirement results in the use of large hydraulic cylinders to raise the apparatus, due to the overall length and weight of each opener assembly. This hydraulic equipment is costly and is demanding of resources (i.e., hydraulic power) from other portions of the tractor and seeding implement.
There is a need, therefore, for improved arrangements in precision hoe openers that improve the accuracy of the seeding operation. There is a particular need for a precision hoe opener configuration that applies forces to the ground engaging tool and the packing wheel to improve seeding depth and accuracy.